Measurement of forces by means of a force platform apparatus is well-known in the art and in one desirable form the force platform means may be employed in measuring human dynamics and is commonly referred to as a "Biomechanics Platform". The field of application of force platforms including biomechanics platforms has been rapidly widened in recent time and extends into fields of specialized medical application, sports application, running dynamics and the like.
Strain signals induced by forces and torque applied to a platform such as a biomechanics platform are electrically sensed and then transmitted to receiver means to provide a suitable record. It is essential that a high degree of selectivity and accuracy be achieved in the sensing and transmission of strain signals. In this connection, difficulty has, in some instances, been experienced due to the fact that erroneous strain signals may be sensed and transmitted. Erroneous signals thus sensed are commonly referred to as "cross talk" and may detract materially from the accuracy of measurements obtained.
There are various forms of cross talk and the invention is particularly concerned with one form of cross talk which may be defined as erroneous strain signals resulting from deformation of a top plate due to applied loads. This type of cross talk may be principally experienced by the horizontal force sensing channels, but may also be experienced in vertical force channels and in moment sensing channels.
Various proposals have been made for dealing with the problem of cross talk induced by deformation of a top plate member, but none have been effective and there presently exists a need for improved accuracy in force measurements using force platforms.